A wheel hub joint unit is known from Document DE 10 2004 054 901 A1. The known wheel hub joint unit comprises a wheel hub—constant velocity rotary joint unit, in which a wheel hub having a through-opening having inner shaft teeth is clamped to the joint outer part of a constant velocity rotary joint. In this case, the inner shaft teeth of the wheel hub engage with the outer shaft teeth of the joint outer part, and a double-row wheel bearing is disposed on the wheel hub and the double-row wheel bearing is clamped between wheel hub and joint outer part by means of a clamping screw.
FIG. 4 shows a schematic diagram of a wheel hub joint unit 30, showing a pivot point 22 of a constant velocity rotary joint 2 disposed as a distance a′ from a mounting disk 12, the mounting disk 12 being provided for mounting a wheel rim and/or a brake disk of a drive wheel, and the mounting disk 12 also being designated as wheel hub flange. Such a wheel hub joint unit 30 can be used both for a front wheel drive and also for a rear wheel drive. However, the large distance a′ between the pivot point 22 of the constant velocity rotary joint 2 and the mounting disk 12 of the wheel hub 5 is particularly disadvantageously noticeable when the known wheel hub joint unit 30 is to be used in a front wheel drive.
In this case, the front wheel which is mounted with its wheel rim on the wheel disk 12 is pivoted about an axis 21 of the knuckle joint. However, this axis 21 is remote from the mounting disk 12 by a distance a, which is significantly shorter than the distance a′ of the pivot point 22 of the constant velocity rotary joint 2. In this case, in order to ensure drive via the drive shaft 8, care must additionally be taken to ensure that the drive shaft 8 cooperates axially displaceably with the constant velocity rotary joint 2 in order to compensate the ensuing length difference for the drive shaft of different distance between a and a′ when the wheel hub 5 pivots about the axis 21 of the knuckle joint.
FIG. 5 shows a schematic cross-section through a wheel hub joint unit 30 according to FIG. 4 with further details. A double-row bearing 6 is disposed as wheel bearing 3 on a lateral surface 29 of the wheel hub 5. To this end, a ball bearing seat 23 is incorporated in the lateral surface 29 of the wheel hub 5, on which a first ball bearing row 16 rolls and the balls of the ball bearing row 16 are held in position by a ball bearing cage 28. In addition, the lateral surface 29 of the wheel hub 5 has a press fit 17 with an inner race 18 of a second ball bearing row 19. The balls of the second ball bearing row 19 roll on its inner race 18, which is pressed on to the ball bearing seat 23.
A double-row bearing is understood in this context as a double- or multi-row wheel bearing, which preferably comprises roller bearings such as balls or tapered rollers or cylindrical rollers and is preferably configured as a double angular ball bearing or a double tapered roller bearing.
The two ball bearing rows 16 and 19 have a common ball bearing outer race 20, which is connected to a rear wheel suspension in the case of a rear wheel drive and cooperating with a front wheel suspension via knuckle joint in the case of a front wheel drive. As mentioned above, the joint outer part 4 of the constant velocity rotary joint 2 is drawn into a central bore of the wheel hub 5 with the aid of a central clamping screw 24 along shaft teeth 27 of the joint outer part 4, and a radial stop face 31 pretensions and fixes the inner race 18 of the double-row bearing 6.
Known from the Document DE 100 29 100 A1 is a bearing arrangement for a drive wheel, and a double-row bearing is likewise disposed between a wheel hub and a constant velocity rotary joint and merely a hub-side ball bearing row of the double-row bearing rolls on the wheel hub and a joint-side ball bearing row rolls on the joint outer part and the expensive shaft teeth between wheel hub and joint outer part are replaced by a non-detachable plastic deformation of roughened surfaces.
Finally, a wheel bearing arrangement is known from the Document WO 2006/092121 A1, in which a double-row bearing for mounting a drive wheel is disposed between a wheel hub and a constant velocity rotary joint and merely the shaft teeth between wheel hub and joint outer part are replaced by front teeth.
The known wheel hub joint units 30 have the disadvantage that they require a large installation depth axially, so that their use particularly for front wheel drives is problematical, since the pivot point 22 of the constant velocity rotary joint 2 cannot align with the axis 21 of the knuckle joint as shown in FIG. 4. A further disadvantage is that a plurality of parts such as a wheel hub 5, a joint outer part 4, and ball bearing rows 16 and 19 are held together by a central clamping screw 24 or by plastically deformed surfaces. This is complex to manufacture and costly.
In view of the foregoing, it is at least one object of the invention to provide a wheel hub joint unit, which has a more compact structure, manages with fewer components, and in particular for a front wheel drive, allows improved cooperation between constant velocity rotary joint and knuckle joint. In addition, other objects, desirable features, and characteristics will become apparent from the subsequent summary and detailed description, and the appended claims, taken in conjunction with the accompanying drawings and this background.